Design concepts for digital television transmitters

Standards for the transmission of digital terrestrial television services are not yet finalised in either Europe or North America, however enough work has been done to facilitate the development of digital television transmitter design. Initial studies have shown that in the USA, where simulcasting and broadcast coverage areas are to be maintained, high power transmitters utilising RF tube based products will be required. However, in Europe lower power systems using solid state transmitter technologies will fulfil most requirements. This paper will discuss the design techniques necessary for solid state digital transmitters, using both (OFDM), orthogonal frequency division multiplex and (8-VSB) 8-level vestigial sideband modulation. The design philosophies will be considered in terms of modulation considerations, system requirements, linearity correction and efficiency